1. Field of the Invention
This invention relates to one-piece flashings pre-formed to fit against building surfaces at certain multi-surface intersections, especially at a common corner where several of the surfaces meet and where the possibility of water infiltration has heretofore been particularly likely to occur.
2. The Prior Art
Standard practice to prevent water infiltration at an intersection of several surfaces on structures, such as houses and other buildings, has been to create rigid, multi-piece flashings on the job by bending pieces of sheet metal during the construction or repair of such structures. The assembled flashings are then fitted against the intersecting building surfaces with at least part of at least one of the sheet metal pieces overlapping part of another. The joints between overlapping pieces are sealed by caulking material or the like. Although construction of these multi-piece flashings is time-consuming and difficult to do, they have been found to be unavoidable where the intersection to be sealed requires the flashing to have more than two panels.
Not only is a three-panel flashing inherently difficult to form on the job, especially where the arrangement of the panels is such that the flashing cannot be cut as a unitary structure from one piece of sheet metal, but the intersection to be protected requires that at least one of the three panels intersect at least one of the other panels at an angle other than a right angle. This is due to the fact that at least one of the panels is in a plane parallel to a roof surface, and at least one other panel is parallel to a surface that intersects the roof surface at the non-right angle. In addition, the non-right angle may have a variety of values according to the design of the building, since it is common for roofs on different buildings, and even on the same building, to have different slopes. This further increases the difficulty of forming the flashing of multiple pieces in advance of construction of the building and taking it to the job site ready to install.
Another serious problem in multi-piece flashings is that, over a period of time, the caulking tends to break down and lose its adhesion to the surface with which it is supposed to bond. This breakdown can occur at any time, and it is not uncommon for it to occur within four or five years, or sometimes less, from the date the caulking was applied. If that happens and a substantial amount of moisture works its way into the building as a result, the damage to the building can be substantial. Water is particularly likely to infiltrate the building at a common corner where three building surfaces intersect.
One way that the building trades responsible for initial construction or repair of the parts of a building where such infiltration is likely to occur have tried to prevent it is by applying a lot of caulking material as a coating on potential trouble spots. Even if that works as a technique for long-time prevention of water infiltration, the area thus coated is likely to display an unsightly agglomeration of caulking material.
It is an object of this invention to provide one-piece, pre-formed flashings, each having a shape that fits certain surface intersections on a building.
It is another object to provide one-piece flashings shaped to fit standard surface intersection angles on a building to achieve economy of scale by manufacturing such flashings in quantity.
A further object is to provide one-piece flashings comprising at least three intersecting panels to fit a building at the intersection of three building surfaces.
Another object is to provide one-piece flashings formed to fit the intersection of vertical building walls with roofs intersecting those walls at certain standard slopes.
Yet another object of this invention is to provide a one-piece flashing comprising a plurality of panels of material impervious to water, each of the panels having first and second edges that radiate from a common location, the first and second edges of each of the panels being joined watertight respectively to the first edge of the panel on one side thereof and to the second edge of the panel on the other side thereof, the common locations of all of the panels being substantially at a watertight corner, and the panels being angularly displaced from each other with at least one of the panels being displaced from at least one other of the panels by an angle other then 90xc2x0.
Still another object is to provide a self-supporting, one-piece flashing to be fitted against at least two flat, intersecting, non-coplanar surfaces of a building to prevent infiltration of water into the building, said flashing comprising: first, second, and third panels of water-tight, weather-resistant material, each panel comprising first and second edges that converge toward a common location and a third edge that forms a respective part of the periphery of the flashing, each of said first and second edges of each panel radiating out from the common location to the respective part of the periphery of the flashing and being joined watertight to respective proximal second and first edges of each of the adjoining panels on both sides thereof with the common location of each panel being closely adjacent to and joined watertight to the common location of each of the other panels to form a watertight common corner, at least two of the panels being substantially flat, and at least one of the panels intersecting another of the panels at an angle other than perpendicular, the flashing being watertight from the watertight common corner outward along each of said panels and each of said edges thereof.
Another object is to provide a pre-formed flashing for preventing water infiltration at the intersection of surfaces of a building, said flashing comprising: a first water-impervious panel that has first and second edges that converge toward a first common location; a second water-impervious panel that has first and second edges that converge toward a second common location; a first water-impervious region of intersection joining the first edge of the first panel to the first edge of the second panel, the second panel being angularly displaced at a first angle with respect to the first panel; a third water-impervious panel having first and second edges; a second water-impervious region of intersection joining the first edge of the third panel to the second edge of the second panel; a third water-impervious region of intersection joining the second edge of the third panel to the second edge of the first panel; at least a portion of the third panel being angularly displaced at a second angle with respect to the first panel and at least a portion of the third panel being angularly displaced at the second angle with respect to the second panel, whereby the first, second and third panels and the water-impervious regions joining those panels together define a common corner impervious to water.
Yet a further object is to provide a method of producing a self-supporting, multi-panel, water-impervious flashing comprising the steps of: heating a quantity of plastic at least sufficient to constitute the flashing; and forming the heated plastic into a desired shape that includes at least three panels, each not substantially thicker than xe2x85x9xe2x80x3 and oriented with respect to each other such that they intersect at a common watertight corner.
Those who are skilled in the technology with which this invention deals will recognize further objects after studying the following description.
This invention comprises a one-piece flashing formed with first and second panels joined together, watertight, at a first angle along a first line of intersection. The first angle may be a right angle or it may be the angle between a sloping roof and a vertical wall. The flashing further includes a third panel that makes a watertight junction with the first panel along a second line of intersection, where the first and third panels meet at a second angle. The third panel also makes a watertight junction with the second panel along a third line of intersection and at a third angle, and the three lines of intersection meet at a common point. It is essential that the panels and all of the junctions between the panels along all of the lines of intersection, and especially at the common point, be impervious to water. This can be accomplished by forming the flashing as a unitary structure, such as by stamping it or molding it, and, if necessary, forming permanent seals at any abutting edges created during the formation of the flashing.
The angles formed at the intersections of the three panels are determined by the angles at intersections between surfaces of the structure against which the flashing must fit. One of the panels typically is in virtual surface-to-surface contact with a portion of the roof of the building and another of the panels is in virtual surface-to-surface contact with a vertical wall intersected by the roof. The third panel can be in virtual surface-to-surface with another wall, or it can be free-standing, but still making angles with the other panels, and, together, these panels and the water-impervious regions of intersection that join them together prevent water from infiltrating at the common point where the panels meet.
The invention will be described in greater detail in connection with the following drawings.